If I saw a man who was not under my charge, taking up a tumbler of poison, I should not be guilty of any crime by not stopping him. I am under no legal obligation to protect a stranger.
That is probably what the priest and the Levite of the parable said to themselves.
A still more emphatic example is in the Digest of Criminal Law, by Justice Sir James Stephen, 1887, p. 154. Reg. v. Smith, 2 C. and P., 449:
A sees B drowning and is able to help him by holding out his hand. A abstains from doing so in order that B may be drowned, and B is drowned. A has committed no offence.
It appears, from a footnote, that this case has been discussed in a striking manner by Lord Macaulay in his notes on the Indian Penal Code, which I have not yet been able to consult.
Enough has been written elsewhere by myself and others to show that whenever public opinion is strongly roused it will lead to action, however contradictory it may be to previous custom and sentiment. Considering that public opinion is guided by the sense of what best serves the interests of society as a whole, it is reasonable to expect that it will be strongly exerted in favour of Eugenics when a sufficiency of evidence shall have been collected to make the truths on which it rests plain to all. That moment has not yet arrived. Enough is already known to those who have studied the question to leave no doubt in their minds about the general results, but not enough is quantitatively known to justify legislation or other action except in extreme cases. Continued studies will be required for some time to come, and the pace must not be hurried. When the desired fulness of information shall have been acquired then, and not till then, will be the fit moment to proclaim a ‘Jehad,’ or Holy War against customs and prejudices that impair the physical and moral qualities of our race.